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src/sparse-0.4.4/perl/t/target-arm/cpu.h  view on Meta::CPAN

 * defines as PL0 (user), PL1 (fiq/irq/svc/abt/und/sys, ie privileged), and
 * PL2 (hyp). The other level which has Read and Write bits is Secure PL1
 * (ie any of the privileged modes in Secure state, or Monitor mode).
 * If a register is accessible in one privilege level it's always accessible
 * in higher privilege levels too. Since "Secure PL1" also follows this rule
 * (ie anything visible in PL2 is visible in S-PL1, some things are only
 * visible in S-PL1) but "Secure PL1" is a bit of a mouthful, we bend the
 * terminology a little and call this PL3.
 *
 * If access permissions for a register are more complex than can be
 * described with these bits, then use a laxer set of restrictions, and
 * do the more restrictive/complex check inside a helper function.
 */
#define PL3_R 0x80
#define PL3_W 0x40
#define PL2_R (0x20 | PL3_R)
#define PL2_W (0x10 | PL3_W)
#define PL1_R (0x08 | PL2_R)
#define PL1_W (0x04 | PL2_W)
#define PL0_R (0x02 | PL1_R)
#define PL0_W (0x01 | PL1_W)

#define PL3_RW (PL3_R | PL3_W)
#define PL2_RW (PL2_R | PL2_W)
#define PL1_RW (PL1_R | PL1_W)
#define PL0_RW (PL0_R | PL0_W)

static inline int arm_current_pl(CPUARMState *env)
{
    if ((env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_USR) {
        return 0;
    }
    /* We don't currently implement the Virtualization or TrustZone
     * extensions, so PL2 and PL3 don't exist for us.
     */
    return 1;
}

typedef struct ARMCPRegInfo ARMCPRegInfo;

/* Access functions for coprocessor registers. These should return
 * 0 on success, or one of the EXCP_* constants if access should cause
 * an exception (in which case *value is not written).
 */
typedef int CPReadFn(CPUARMState *env, const ARMCPRegInfo *opaque,
                     uint64_t *value);
typedef int CPWriteFn(CPUARMState *env, const ARMCPRegInfo *opaque,
                      uint64_t value);
/* Hook function for register reset */
typedef void CPResetFn(CPUARMState *env, const ARMCPRegInfo *opaque);

#define CP_ANY 0xff

/* Definition of an ARM coprocessor register */
struct ARMCPRegInfo {
    /* Name of register (useful mainly for debugging, need not be unique) */
    const char *name;
    /* Location of register: coprocessor number and (crn,crm,opc1,opc2)
     * tuple. Any of crm, opc1 and opc2 may be CP_ANY to indicate a
     * 'wildcard' field -- any value of that field in the MRC/MCR insn
     * will be decoded to this register. The register read and write
     * callbacks will be passed an ARMCPRegInfo with the crn/crm/opc1/opc2
     * used by the program, so it is possible to register a wildcard and
     * then behave differently on read/write if necessary.
     * For 64 bit registers, only crm and opc1 are relevant; crn and opc2
     * must both be zero.
     */
    uint8_t cp;
    uint8_t crn;
    uint8_t crm;
    uint8_t opc1;
    uint8_t opc2;
    /* Register type: ARM_CP_* bits/values */
    int type;
    /* Access rights: PL*_[RW] */
    int access;
    /* The opaque pointer passed to define_arm_cp_regs_with_opaque() when
     * this register was defined: can be used to hand data through to the
     * register read/write functions, since they are passed the ARMCPRegInfo*.
     */
    void *opaque;
    /* Value of this register, if it is ARM_CP_CONST. Otherwise, if
     * fieldoffset is non-zero, the reset value of the register.
     */
    uint64_t resetvalue;
    /* Offset of the field in CPUARMState for this register. This is not
     * needed if either:
     *  1. type is ARM_CP_CONST or one of the ARM_CP_SPECIALs
     *  2. both readfn and writefn are specified
     */
    ptrdiff_t fieldoffset; /* offsetof(CPUARMState, field) */
    /* Function for handling reads of this register. If NULL, then reads
     * will be done by loading from the offset into CPUARMState specified
     * by fieldoffset.
     */
    CPReadFn *readfn;
    /* Function for handling writes of this register. If NULL, then writes
     * will be done by writing to the offset into CPUARMState specified
     * by fieldoffset.
     */
    CPWriteFn *writefn;
    /* Function for doing a "raw" read; used when we need to copy
     * coprocessor state to the kernel for KVM or out for
     * migration. This only needs to be provided if there is also a
     * readfn and it makes an access permission check.
     */
    CPReadFn *raw_readfn;
    /* Function for doing a "raw" write; used when we need to copy KVM
     * kernel coprocessor state into userspace, or for inbound
     * migration. This only needs to be provided if there is also a
     * writefn and it makes an access permission check or masks out
     * "unwritable" bits or has write-one-to-clear or similar behaviour.
     */
    CPWriteFn *raw_writefn;
    /* Function for resetting the register. If NULL, then reset will be done
     * by writing resetvalue to the field specified in fieldoffset. If
     * fieldoffset is 0 then no reset will be done.
     */
    CPResetFn *resetfn;
};